


Birthday

by Suliana



Category: Undertale (Video Game)
Genre: Brotherly Love, Fontcest, I hate tagging, I seem to write a lot of angst, SFW version, Self-Harm (implied), but its ok, collaring (kink), falling down - Freeform, happy ending i swear, platonic, secret-santa gift-fic, there's fluff too
Language: English
Status: Completed
Published: 2018-01-15
Updated: 2018-01-15
Packaged: 2019-03-05 00:28:47
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,054
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13376274
Author URL: https://archiveofourown.org/users/Suliana/pseuds/Suliana
Summary: Fell's relationship with his brother is about to change.Or:AND NOW FOR SOMETHING COMPLETELY DIFFERENT.





	Birthday

**Author's Note:**

  * For [FelliSkelli](https://archiveofourown.org/users/FelliSkelli/gifts).



> Dear Skelli, behold! I give to you your UT!SS2017 thingie. Posted a little early because hey, its the 15th already somewhere. 
> 
> You asked for "Fellcest, something sweet and romantic, with dom Edge" - the added challenge that it needs to be SFW. So, again, behold! Little angst, all the fluff, and Edge in leather pants. What's not to love?
> 
> I headcannon Papyrus to be 6.5-7' tall, and Sans to be 4.5-5" tall. I like me some size differences.

Slipping down the hallway, Papyrus stepped carefully to avoid the third floorboard on the left that squeaked when stepped on.  Not that it really mattered, when Sans was sleeping, he was dead to the world.

Unless he was caught up in another nightmare.  

Pushing the bedroom door open, he peered in, doing his best to block as much of the dim light as he could with his body.  

His bed was a mattress on the floor, a decision Papyrus had made for him a few years past after a nightmare had sent him falling.  He took the crack to his older brother's skull as a personal affront, as a failing, and the frame had vanished the next day while Sans had gone to his sentry station.  His brother hadn't commented on it at that point, or ever, and Papyrus hadn't bought it up himself.

Their relation was... Papyrus had once found a magazine in the dump.  It had been full of human girls giggling about human boys, makeup and relationship advice, folded papers that held noxious samples of perfume.  One of the articles had been written candidly about relationships in general, just saying they were complicated.

That was an understatement, but adequate.

His brother was curled around a pillow, his back to the doorway.  The air to the room was still, thankfully.  Sans tended to lose control of his magic during a nightmare episode, and it would inevitably leave some of his furniture floating.  Not that he had much left - his desk, chair and dresser had all vanished into the guestroom after a particularly bad night that had left him with a broken radius and Papyrus with a reaction headache.  Sans had never commented on that, either, instead just letting himself into the guestroom to get clean clothes as needed.

Satisfied all was well, Papyrus let the door close with a soft  _click_ behind him, heading to his own room.  Door shut, he stripped off his chest-piece, hanging it over his chair.  Gloves followed, folded neatly and set on his desk.  Socks were kicked off and dumped in the laundry basket.

Safe behind the sturdy walls of their house, safe in his room,  _knowing_ everything around him, Papyrus fell backwards on his bed, arms spread wide.  The mattress squeaked at the impact, the sound gone as fast as it had come.  No one in Snowdin would have believed that their Lieutenant of the Guard would ever be in such a vulnerable position, no matter  _where_ he was located.  

He sighed, throwing an arm over his eye sockets.  Tomorrow...

Tomorrow was his brother's birthday.  

This time last year, he wasn't sure his brother would even still be alive the next day.

* * *

Sans had been strange for the previous few days.  Unsettled.   _Not_ himself.  No puns.  No pranks.  No trips to Grillby's.  

Papyrus had been newly promoted, the brand new Lieutenant, in charge of Snowdin's security, of making sure the safe-zone of the town's borders was enforced and that XP hunters kept their activities well away.  The chest-piece had a near mirror-finish, he had spent so much time buffing it.  He had been so excited, so proud, so... so full of himself... he didn't see any of the warning signs.

It was the week before his brother's birthday, not that it was something celebrated.  Used to tick off another year alive?  Sure.  A measure of strength?  Absolutely.  A joyous occasion?  Not so much.  There wasn't all that much to celebrate in Underfell.  Papyrus had been busy with Undyne, training new recruits and adjusting to working with the mutt clan, out of the house most of the day, often running too late to walk home with his brother.  Not that they would show affection to each other outside of the safe walls of their home, oh stars no, but it eased the burden on his SOUL to know that his 1 HP brother was safe.

He had been later that day than normal, the biting cold that was Snowdin cutting through his cloak.  His scarf flapped behind him, whipping at his vertebrae.  The sentry station had been abandoned when he passed, as he'd expected - it was way past the end of Sans's shift, he'd likely be home, sprawled on the couch watching some random television program.  

There had been some snowfall while he had been in Waterfall with Undyne, and his brother's tracks were clearly visible in the snow.  When he had been younger, smaller, Papyrus had made a game of walking in the same footprints.  As he had gotten older, gotten  _taller_ , it had been Sans who had moved to walking behind, letting his taller younger brother break the way through the ice-crusted snow.  Today, it looked like Sans had struggled with the depth of snow.  The tracks, instead of being clearly distinct, were instead a mess of churned snow with no gaps between individual steps.  Broken holes to the side of the footsteps proper hinted at times the smaller skeleton had stumbled, catching himself in the drifts.  

That was... curious.  The snow wasn't  _that_ deep by Snowdin standards, what had caused his brother to stumble so very many times?  Was he sick?  That would explain just how  _off_ he had been for the past week.  

Papyrus sighed, mentally changing his dinner plans.  Lasagna, while filling and delicious, might not be the best option if Sans was coming down with something.  Soup would be a better option, easier to digest, the magic easier to absorb.  With such low HP, such things were never far from Papyrus's mind.  He would  _not_ lose his brother to his own carelessness.  Snowdin residents would never  _dare_ to attack Sans, not with the knowledge of who would come to collect their own dust.  Yes, soup would be fine for dinner.  Maybe some quick dumplings on top.  

Unlocking the front door was a practiced ritual, the locks being done in a specific order.  Door opened, he stepped through, kicking his boots off as he shut and re-locked it.  He placed his boots on the boot tray neatly, groaning as he dug phalanges deep into the arch of his metatarsals to ease out the kinks of a long day.  Sans's boots... weren't there.  Instead, a wet trail led up the stairs.  

He couldn't help it, he growled.  Really Sans?   _Really?_   He  _knew_ it infuriated him no end to have a mess in the house.  

He suppressed the desire to yell.  He was too damned tired for this nonsense.  Pinching his nasal ridge, he decided to put the soup on first before dealing with his brother.  Can opened ( _stars_ he hated canned soup, but really didn't have the energy for much else) and stove on, he put the pot on and set a quick timer.  Deciding against the dumplings, he grabbed a hand towel to throw at his brother and made toward the stairs.

He didn't try to muffle his approach, as he normally would when mad at his brother.  Instead, he let his weariness drag him up, sighing.  The door to his own room was closed, his brother's... 

Huh.  That was strange.  Sans's was open.  Normally, his brother valued his privacy, and usually had it closed and locked, when home alone, just in case.  The light was off though, and Papyrus felt his SOUL tighten.  Was Sans sleeping off whatever illness he had picked up?

He knocked on the door frame before stepping in, hitting the light switch as he passed.  The Sans-shaped-lump on the bed didn't move.  His black sweatshirt was on the floor by the door, and Papyrus resisted the urge to pick it up and hang it up.  This was his brother's space, as much as the mess made him twitchy, it wasn't worth starting an argument over.  

"Sans?" he called, his brusque voice breaking through the otherwise silent room.  

Nothing.

He squinted his sockets, crossing the room silently.  Sans must  _really_ be sick.  Hopefully not so bad he'd have to go to Alphys, Sans had  _never_ gotten along well with the lizard monster.  

He put his phalanges on his brother's shoulders and rolled him onto his back.

Dark, blank sockets met his.  No eyelights, no movements, no sound.  

In that moment, Papyrus knew true fear.  There was only a few things that would send a skeleton monster into a state like that, and, though he doubted the existence of a higher being given the hellhole they lived in, he began praying to anyone, any _thing_ that would listen.  With shaking hands, he ran a single phalange across his brother's cheek.

It came back coated in dust.

No.  NO.  NONONONONO _NONONONONONONONONONONO._

He didn't realize he was howling the word until a hot tear splashed onto his still outstretched arm.  

Sans couldn't Fall Down.  He  _couldn't_.  

"Sans, b-big brother, don't do this," he scrubbed an arm angrily across his sockets, glad in this moment that they had no near neighbors that could possibly hear him.  "Sans, can you hear me?  Stars, stars  _above_ , Sans don't do this.  I can't do this alone.   _Don't_ leave me."

He nearly threw himself onto the mattress, pulling his limp brother into his arms.  He cradled him close, rocking, begging his mantra over and over and over.  Apologies fell from his mouth, desperate promises and tears joining them.  

Empty sockets stared blankly at the ceiling. 

Heaving for air that he didn't strictly need, Papyrus dug his claws into his ulna, needing desperately to ground himself, to concentrate.  " _Think_ , Papyrus.  You can do this," he started encouraging himself as he dug through his memories on what to do if someone had newly Fallen Down.  There was still a chance...

Trembling harder than he'd like, than he'd ever admit, he flicked his wrist  _just_ so, twisting his phalanges as he did.  Sans's SOUL materialized, hovering above his brother's chest.  It was... 

It was not good.  Normally a deep red, the same color as his magic, it had faded to the color of an old brick.  Old, and sickly.  Normally, there were some cracks on the SOUL, but this was Underfell, that was  _normal_.  What was  _not_ normal was the gaping crack that began on the crest of one side and ran diagonally up towards the gently-rounded tip.  Raw, pulsing magic was visible beneath, and Papyrus had to bite back the bile rising in his throat.  "Oh,  _stars_.  Oh, brother.  Why didn't you tell me?" he whispered, reaching out with still-shaking hands to cup and cradle the wounded organ, his styloid process coloring with flushed magic at the tension he was putting on his jaw.  

Papyrus had spent years,  _years_ training to be in the Guard, to  _better_ their place.  He had known, somewhere, that Sans had done the same, working multiple jobs to put them both through school, and eventually dropping out himself so that his little brother could continue.  He knew his brother put his own comfort to the side so that Papyrus could have as many opportunities possible to escape the poverty they lived in.  And they had!  They had beaten the system, and Papyrus had landed himself a cadet position in the Guard.  He had thrown himself into training, gradually becoming colder to his brother in attempt to insulate him from any number of dangers that could befall a 1 HP monster.  

And they had been safe, had moved to Snowdin, had established themselves.  And in all that time... Papyrus realized with a start that he had never realized that Sans had never given up his routine, his multiple jobs.  Had he really been so wrapped up in himself that he had forgotten his own  _brother_?  

He cradled the SOUL delicately in his hands, his brother's skull cradled below in the crook of his folded legs.  Shuddering, he pulled up his magic and let it run into his hands, into his brother's SOUL.  He focused on everything pleasant, happy, everything positive he could think of, his desperation, his fear, his apologies.  He focused, he  _pushed_ until he had no more magic left to push.  

He opened his eyes, not sure when they had closed, and squinted at the precious cargo he held.  It... it looked better?  Redder, for sure, beads of raw magic and tears standing brightly on its surface.  The crack didn't seem as deep, but it was hard to tell if it the magic within was still exposed.  His eyesight blurred for a moment, testament of just  _how_ much magic he had used.  He glanced down.

There was no change.  Empty sockets. 

He flicked his wrist again, and the SOUL flickered as it vanished, back to his brother.  He cupped his brother's face with both hands, cringing as they brushed off more dust.  It... it hadn't worked.  It  _hadn't_ worked.  

Papyrus did something he hadn't done since he had been a babybones, when Sans had told him solemnly that it wouldn't help.

He cried.

He sobbed, his voice hitching in his throat as he cradled his brother's unresisting form to his chest.  For how long he did, he had no idea, loss to everything but his grief.  Once a monster Fell Down, the odds of them coming back... they weren't good.  

Papyrus had enough dust on his hands.

He murmured to the Angel herself as he hauled the discarded blanket from the bed over his lap, over Sans.  He stroked at his brother's coronal suture, a thumb brushing gently under the empty socket.  His skull tilted back until it rested against the wall, scrunching his sockets closed again.  

Grief and exhaustion hit him, and sleep tugged at him.  

He had succumbed for stars knew how long, only coming back to himself when he heard the soft  _whuff_.

His sockets snapped open, eyes flaring red magic so agitated it colored the air around him.  He whipped his head to either side, trying to place where the sound came from.  

The room was empty, devoid of anyone save himself... and  _Sans._

His own SOUL clenching, he looked down... 

And a single, hazy eyelight blinked up at him.

"B-brother?" He did  _not_ stutter.

Sans blinked slowly, eyelight flickering before stabilizing.  Not quite fully aware of himself yet, he whined in the back of his throat as Papyrus pulled him back into his lap, holding him like he would a babybones.  Gentle words left Papyrus's mouth, words themselves that neither would remember the next day, but their intent, their  _meaning_ they would.  

The next day had dawned far too bright, far too early.  Papyrus, having just held his brother all night, terrified that he might Fall again, had sent a text to Undyne, saying he needed a few days to handle some familial matters.  The fish monster had responded with a rude emoji, telling him to take the week if he wanted since he had already hit overtime for the week and her budget was going to be shot to hell.  

Sans had woken slowly, blinking his sockets slowly as he placed where he was.  Papyrus still held him across his lap, his skull cradled against his brother's clavicle.  He was warm, but why was he here?  He didn't remember much of the last few weeks, to be fair, but he had just assumed he was coming down with something.  Why were there tear stains on Papyrus's mandible?  What happened?

He groaned as he shifted, his brother's arm immediately tightening around him.  "Wha-wha' 'appened?" he slurred, not liking how distant, how fuzzy he felt.  He managed to tilt his head up enough to see his little brother's face, and the pain, the  _fear_ that, for once, wasn't concealed, made his SOUL ache.  

Papyrus must have caught his flinch at the stab of pain, adjusting the smaller skeleton a bit so that his skull was against his sternum.  He set his chin on the smooth curve of San's skull, purring softly in content in knowing his brother was, at least for now, all right.  "You... you started to Fall Down, Sans.  You  _did_ Fall Down."

A whimper caught in his brother's throat, the smaller form tensing against him.  He ran a soothing hand over his spine, gently thumbing each curve of his thoracic vertebrae, lingering in the sensitive intercostal spaces.  He worked his way up, slowly, unspeaking, until he reached the cervical vertebrae.  The soothing touches stole away Sans's words, and he began purring himself, stuttering as clawed phalanges stroked sensitive areas with surprising care.  

"Brother, I have done all I have  _for_ you, and I know the same is true of you.  I can't,  _can't_ do this  _without_ you.   We need to take more care of each other, no one else here will."  He focused his slowly recovering magic pushed his intent through his claws.  The bone-on-bone contact with his brother, ever receptive to his brother, meant the intent hit him with no restrictions, and his purring cut off completely as he shuddered with the force of the impact.   _/ peace / comfort / companionship / family / love /_ poured over him, one emotion running into another into another so quickly and seamlessly it made the smaller skeleton's head spin.  

This... this is what his little brother felt for him?  Focusing was hard with so much pressing against him at once, but Sans drew up his own magic and pushed his own back at his brother, the contact being a two-way street.

The taller skeleton inhaled sharply as his brother turned the tables on him, letting the magic soothe his frayed nerves.  

They had stayed like that for most of the day, tears coming from both, haltingly talking, realizations being realized, promises being made.

* * *

Papyrus arched his back off the bed to ease out kinks, to shake away memories.  He rolled off and stepped to his dresser, pulling open the top drawer.  Buried beneath his socks was a small box, shallow, maybe a handspan across.  

He sat back on the bed, considering it.  For the last month, he had been pushing his magic into the box's contents nightly, protective runes and sigils etched onto its surface carefully.  It nearly  _glowed_ from the amount of magic it was imbued with.

It would be enough.  

It  _would_ be.

He set it next to his pillow and stretched out, tugging up his quilt.  The morning would come soon enough.

* * *

 

And it did.   

Papyrus toed the door to his brother's room open, a glass of milk (healthy bones, after all!) and a plate of toast juggled between his hands.  He set the dishware on the floor next to the mattress and settled himself, his now empty hand settling on his brother's cervicals and stroking lightly.  Visible socket opening slowly, a red eyelight squinted up at him before his older brother shifted his skull enough so his face was fully exposed.  He gave his brother a crooked smile as he stretched not unlike how Doomfanger would.  Vertebrae popped and cracked, and he pushed himself up on his elbows.

"Happy birthday, brother," Papyrus gave him an appraising look, grabbing the milk and pushing it into his hand.  "How are you feeling this morning?"  The questioning, benign on the surface, had become a morning ritual for the brothers, letting Papyrus gauge how well Sans was doing, giving him a chance to pick up any warning signs his brother wouldn't address himself.  

Licking milk from his fangs, Sans handed the cup back and pushed himself all the way up, sitting so he was leaning against his brother.  In the last year, it had become more and more clear that Sans  _needed_ the contact as a grounding point.  Hours spent outside in Snowdin, in the sheer  _hostility_ of Underfell, wore away brutally at his brother's psyche, and Papyrus was more than willing to give him as much time before and after a day out and about to find himself as he needed.  Within the walls of their house, they were free to do as they wanted, as they  _needed_ , and stars help  _anyone_ who try to interfere with that.

"Not so bad, Boss," Sans admitted, cracking the magic in his joints.  'Boss' had been Undyne's suggestion, surprisingly - a way for Papyrus to keep the town on its toes, for Sans to emphasize his importance to his brother, while at the same time preserving Papyrus's authority without the smaller brother accidentally undermining it.   _That_ had been an interesting conversation, to be sure.  "Little stiff, nothin' bad."  

Papyrus gave a crooked smile down at his brother, then reached into his jacket pocket and pulled the box from the night before out.  He held it tightly in both hands, flipping it over as he looked down to his brother's response.  

Sans's sockets had gone wide, eyelights shrinking to points.  "Wha- huh?"  He could be so verbose at times.

The taller skeleton shoved the box into his lap, actions betraying his nerves.  "Happy birthday, Sans.  I... I hope you - I hope this is acceptable."

Magic flushed across his brother's cheekbones, and he ducked his head in an attempt to hide it.  "Boss, bro, you didn' have ta-"

"Open it, runt."

Sans flipped the box over, mirroring his brother's motions of a few moments past.  He ran a claw carefully around the edge, then pulled the lid off.  His eyelights sparked, then constricted further.

A leather collar sat in the bottom half of the box, its d-ring's chrome bright against the darkness of the leather.  With trembling hands, Sans pulled it out.

Touching it was like being at the breakpoint of a tsunami of emotions and magic.   _/ pride / safety / MINE / family / security / MINE / protection_   _/_ hit him, all feeling distinctly of his brother's magic.  Followed close after was the magic of a dozen or more protective sigils, the scripted magic reaching out, touching his own, keying to him and him alone.  His eyelights guttered out at the force of the magic, the idea that his brother had put so much work, so much  _effort_ into this... for him... blowing his mind.  Papyrus had  _never_ been that good at sigil and rune magic, being the better brother by far at offensive, responsive and reflexive magic.  So much... for him...

His SOUL felt lighter than it had in a long time.

Papyrus sat on his hands, watching the emotions on his brother's face as the magic in the collar keyed itself to him.  It had taken him the past month to get all the spells right, to key them to his brother, to make  _sure_ it was clearly evident just exactly what they were.  Sure, to the rest of Snowdin, they'd see the collar as another way that Papyrus controlled his brother, exerted his dominance.  Well, they weren't totally wrong.

Sans shivered next to him, running his phalanges over the supple leather.  His eyelights had widened, looking younger, more relaxed than he had in years, even with the dark smudges beneath the sockets.  "Ya... will ya help put it on?" his blush darkened, and he thrust out his hand, looking away in embarrassment.

A claw under his chin drew his gaze back, and Papyrus took the collar from the outstretched hand.  It was the work of but a moment to get it around and fastened over his brother's delicate cervicals.  Sans shivered again, going boneless against his taller brother as the magic finished keying itself.  He lost himself to the sensations, safe in a place where nothing could hurt him, content in the knowledge that it was his brother's arm around him.  Here he didn't have to worry about kill or be killed, about the dust that was on his hands, that was in the air.  Here it was just him and his brother.

Papyrus sat and watched, completely content, as his brother came back to himself.  Chuckling at the wonder clearly evident on his face, he placed a chastely gentle kiss to his brother's frontal bone and let him cuddle up against him.  There was safety woven into the magic, comfort... and a promise.  

The last year had led to a lot of SOUL-searching, a lot of consideration, and all of that had been pushed into the weaving of the runes.  It would be up to his brother to make the choice, but, one way or another, just the knowledge that he was  _safe_ was enough.

It would always be enough.  

The collar would show to  _everyone_ that it was enough, and Angel help anyone who thought otherwise.

**Author's Note:**

> I totally want to make a NSFW version of this, where the relationship isn't as platonic... :thinking:
> 
> alternate name: Collar (but that would have totes blown the entire story)
> 
> I hope you like it!


End file.
